1. Field of the Invention
The present invention relates to a power conversion device such as ac/dc converter whose function is to convert DC of a DC power supply, e.g., battery to AC, or to convert AC to DC; or inverter whose function is to convert power-frequency AC to AC of different frequency.
2. Description of the Related Art
A power conversion device such as ac/dc converter functioning to convert DC to AC, or AC to DC, or inverter functioning to convert power-frequency AC to AC of different frequency is comprised of: a power conversion module, which performs power conversion between DC and AC, or between power-frequency AC and AC of different frequency; and a control circuit board into which a control circuit to control this power conversion module is integrated. To meet needs of higher performance and downsizing of a power conversion device, a power conversion module and a control circuit board is packaged in one case, whereby downsizing of devices is achieved.
A large current is controlled at the power conversion module, so that the sharp temperature rise occurs due to heat generation, the power conversion module coming to be at a high temperature. In addition, many parts having intolerance for high temperature are used as components forming a control circuit. Accordingly, in the device, it is necessary for the control circuit board to be constructed so as to be free from the effect of heat of the power conversion module.
Downsizing a power conversion module has been popularized with the advance of technology, and needs of downsizing a power conversion device that employs such a power conversion module is increasing. To achieve the downsizing of the power conversion device, a power conversion module and a control circuit board are constructed as an integral whole. In such a construction, thermal insulation is secured between a power conversion module and a control circuit board, and heat having been generated is radiated to outside efficiently so that the control circuit board is free from the generated heat of the power conversion module, whereby it becomes possible to achieve a downsized power conversion device.
To make a control circuit board less affected by generated heat of a power conversion module, a construction is disclosed in, for example, the Japanese Patent Publication (unexamined) No. 014169/2000.
This construction, as shown in claim 1 and FIG. 1 of the Japanese Patent Publication (unexamined) No. 014169/2000, includes an armored case that contains therein a power conversion module and a control board; a radiator fin to which the power conversion module is fixed; and a heat insulating partition wall that is located inside the armored case and between the control board and the radiator fin.
According to such construction, the heat effect of the power conversion module on the control circuit board is thermally interrupted with the heat insulating partition wall. Even if there is no large spacing between the power conversion module and the control circuit board, the temperature rise of a control circuit board is suppressed, thus enabling to achieve the downsizing of device.